Salem Harbor is a harbor in northeastern Massachusetts spanning an area north and south of Salem. Historically the Salem Harbor was the site of one of the major international ports in the colonies. During the American Revolutionary War, merchant ships were enlisted as privateers, an important role to augment the ill-prepared Continental Navy. In 1790, Salem Harbor was a world-famous seaport and sixth-largest in the United States of America. Now the harbor is used for commercial and recreational purposes.